/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.chukwa.datacollection.adaptor.filetailer;
import java.util.Arrays;
import org.apache.hadoop.chukwa.ChunkImpl;
import org.apache.hadoop.chukwa.datacollection.ChunkReceiver;
/**
* A subclass of FileTailingAdaptor that reads UTF8/ascii files and only send
* chunks with complete lines.
*/
public class FileTailingAdaptorPreserveLines extends FileTailingAdaptor {
private static final char SEPARATOR = '\n';
@Override
protected int extractRecords(ChunkReceiver eq, long buffOffsetInFile,
byte[] buf) throws InterruptedException {
int lastNewLineOffset = 0;
for (int i = buf.length - 1; i >= 0; --i) {
if (buf[i] == SEPARATOR) {
lastNewLineOffset = i;
break;
}
}
if (lastNewLineOffset > 0) {
int[] offsets_i = { lastNewLineOffset };
int bytesUsed = lastNewLineOffset + 1; // char at last
// offset uses a byte
assert bytesUsed > 0 : " shouldn't send empty events";
ChunkImpl event = new ChunkImpl(type, toWatch.getAbsolutePath(),
buffOffsetInFile + bytesUsed, Arrays.copyOf(buf, bytesUsed), this);
event.setRecordOffsets(offsets_i);
eq.add(event);
return bytesUsed;
} else
return 0;
}
}